Laney VH100R big buzz - Youtube

[Peter777]

Hello Everyone !
I'm broken. I do not know what is going on. I've got issue with Laney 100VHR, it buzzes on distortion channel, check my Youtube video :
YouTube- 1
Anyone can help me ?! I checked tubes, replaced them, I noticed that after pulling out the tube from V4 (2nd gain stage clean channel) slot the buzz it's very quiet, just a little bit but equalizer on both channels doesn't work and second clean channel with little overdrive. When I put this tube back, the buzz is horrible again like on video. Anyone can help me ?! Maybe ground issue in my whole house ?! The valve amps are very touchy with ground issue than transistors ?! I've got transistor and there'e everything allright. I will be grateful for help !

[Peter777]

Nobody ?! Tomorrow I will try to replace filter caps in power supply maybe it will decrease buzz from power transformer ... If I will find solution I will post here and maybe I will be able to help anyone in the future ...

[Peter777]

I fixed it. I was broken because I bought this amp few days ago as a used amp and I paid few hundred euros and Laney was broken. But I fixed it.
I spent whole day today but I fixed it. First I replaced filter caps in power supply +15v. I bought the cheapest caps electrolytic just to check if they are bad. One important message, do not buy cheap caps they make some noises. After replaced nothing has changed. So following schemtic (I googled it) I replaced electrlytic caps on bias path. Also nothing has changed. Then I measured voltage (my amp is from 2002 & schemtic was from 1995) I noticed big differences in voltages on tubes. Carefully I moved wire by wire via electric current tester. And then I grab the interconnect cables (tape with wires inside looks like in pc) and moved it away from fx pcb and I fixed it.
Just moved this tape to opposite side. In place where was the bigger buzz was the place where tape (with signal wire inside) was close to the wire with high voltage current flows on fx board. Now everything is allright. Anyway I hear very little toroid hum, LANEY VH100R has got toroid power transformer. Marschall & Peavey xxl are amps on which I played and there's no toroids PT. But this LANEY kills with sound those 2 amps definately even with this small little toroid sound out of the speakers. Fat sound, versatility and flexibility ! Hope it will helps someone in future !